Pituitary Diseases

Question 1

pituitary tumor with suprasellar extension, what would it compress?

Answer 1

Optic chiasm

Question 2

Superior extension of pituitary tumor can lead to compression on what ?

Answer 2

Firstly the optic apparatus and later the hypothalamus

Question 3

Lateral extension of pituitary tumor will cause what?

Answer 3

Compression or invasion of cavernous sinus can compromise 3rd, 4th, or 6th cranial nerve function, manifest as diplopia in <15% of pituitary tumor ptn

Question 4

What’s the diagnostic test for Acromegaly?

Answer 4

Oral glucose tolerance test ( failure of GH Suppression during an OGTT )

Question 5

After trans-sphenoidal resection pf pituitary. Ptn may develope 2ry hypoadrenalism, and other complications as hypothyroidism, decrease lipido, ADH and GH, ect. What is the most important hormone replacement in such ptn?

Answer 5

Hydrocortisone 10mg/ 5mg/ 5mg to mimic diurnal cortisol profile

Question 6

Necrosis of the femoral head, is a feature of which endocrine disease?

Answer 6

Cushing’s syndrome ( due to osteoporosis)

Question 7

Name medication that causes galactorrhoea?

Answer 7

Metoclopramide ( dopamine antagonist)

Note; dopamine inhibits prolactin release from anterior pituitary

Question 8

If you will switch Hydrocortisone to prednisone. How will you calculate the dose?

Answer 8

Prednisone to Hydrocortisone is 4:1

eg. If ptn takes 20mg Hydrocortisone then should take 5 MG Prednisone

Question 9

Note: What does pituitary apoplexy means? And what’s the C/P?

Answer 9

It means that there is bleeding inside the pituitary tumor

Symptoms of pressure : acute sever headache, visual disturbance, pallor of optic nerve ect.

Question 10

A.ADH syndrome is ass. With what cancers?

Answer 10

Bronchogenic carcinoma, intracranial Neoplasm

Question 11

N. Name the hormones that are secreted from anterior pituitary and their regulation hormones? 5

Answer 11

ACTH ( regulated by CRH ) , TSH ( regulated by TRH ) , prolactin ( regulated by TRH & inhibited by dopamine ), LH & FSH ( regulated by GnRH ) , GH ( inhibited by somatostatin.

Question 12

N. What are the hormones present in posterior pituitary? 2

Answer 12

Oxytocin, Antidiuretic hormone ( vasopressin)

Question 13

N. After examining ptn with suspected acromegaly, what’s the next step in diagnosis?

Answer 13

Check IGF-1 , glucose tolerance test , pituitary MRI

Question 14

N. Name the drug that act as GH receptor antagonist?

Answer 14

Pegvisomant

Question 15

N. How to treat ptn with pituitary microadenoma?

Answer 15

Give dopamine agonists as : bromocriptine ( first choice because it’s cheap ) , cabergoline ( is better but expensive ). To check for response repeat PRL in 1 month

Question 16

N. Name the causes of prolactinemia?

Answer 16

Physiologic ( pregnancy, lactation, nipple stimulation, exercise ) /
Drugs ( anti-psychotic, opiates, cocaine, metoclopramide, methyldopa, cimitidine , verapamil ) /
Other causes: pituitary adenoma or tumor , hypothyroidism, liver cirrhosis, chronic kidney disease

Question 17

N. What are the causes for SIADH?

Answer 17

CNS disorders ; Trauma, stroke, brain metastasize, infection, drugs /
Pulmonary diseases /
Post-pituitary surgery (3-7) days

Question 18

N. How to treat ptn with SIADH?

Answer 18

Fluid restriction, if symptomatic or Na is <110 then hypertonic saline is given very slowly

Question 19

N. What the difference between Cushing disease and Cushing syndrome?

Answer 19

Cushing disease : is pituitary in origin, ACTH dependent while
Cushing syndrome: is adrenal in origin, ACTH independent,
Both have elevated cortisol

Question 20

N, how can dexamethasone suppression test ( dexa is given at 11pm and tested at 8 am ) can differentiate between pituitary source ACTH from ectopic source?

Answer 20

If pituitary origin = the cortisol will be suppressed/ if ectopic = no suppression

Question 21

N. What are the initial tests for diagnosis Cushing syndrome?

Answer 21

24 urine free cortisol + dexamethasone suppression test + late night salivary cortisol

Question 22

N. What’s the treatment for Cushing disease?

Answer 22

Surgery ( best ) , radiation, drugs ( that control the effect of excess cortisol)

Question 23

N. What’s pituitary apoplexy and what’s the first step done in the management?

Answer 23

It’s pituitary hemorrhage, urgent transphenoidal decompression to preserve vision

Question 24

N. How to diagnose diabetes insipidus?

Answer 24

Serum osmolarity >295 with diluted urine, low urine osmolarity ( U:S osmolarity ratio <2 )